Investigating the effect of interatomic distance on friction force through MEMS-AFM based experiment.

[Display omitted] • A microdevice driven by a comb actuator was fabricated using the DRIE process. • The MEMS-based microdevice was integrated onto an AFM. • The AFM was employed to quantify the friction force on the strained Si surface. • The FFM image was consistent with the strain image acquired through FEM analysis. • A 1.2% variation in atomic distance resulted in a 9% reduction in the friction force. Investigations on the influence of the interatomic distance (IAD) on friction are crucial for gaining a better understanding of friction and comprehending the essential nature of graphene friction. We obtained friction force microscopy (FFM) images of strained surfaces to examine how the IAD affects the friction force. First, using microelectromechanical system (MEMS) fabrication techniques, we fabricated a strain-generating microdevice that can generate surface strain on its Si surface by an electrostatic comb actuator. The microdevice was installed in a high vacuum atomic force microscope. Next, FFM measurements were performed on the stress concentration section of the microdevice using a Si cantilever. The driving voltage on the comb actuator was switched on/off for each scan line during a single raster scan. This procedure allowed us to obtain FFM images representing the surface strain (i.e., the IAD variation) by excluding friction/wear-induced disturbances. The FFM images agreed well with the strain distribution calculated by the elastic finite element method analysis. The relative reduction of the friction was approximately 9% against the calculated strain of 1.2%. [ABSTRACT FROM AUTHOR]